If you get a hosting machine of your own, it will operate independently, so it will have its own Operating System and you can later install server side applications directly or script-driven sites via a hosting Control Panel. Although keeping the Os updated isn't always considered fundamental, it can be a rather important task for a number of reasons. A more modern OS version might have better support for specific hardware, so you may get better performance for the sites and web apps that you install. Your server will also be more secure because updates normally include security patches that take care of small problems that may allow unauthorized individuals to access your content. Last, but not least, current script versions, which are also released for both increased security and for additional features, may require a later version of the Os in order to work correctly and with their full capabilities.